The present invention relates to ignition systems for internal combustion engines, and particularly high power, high energy capacitive discharge ignition systems for multi cylinder engines. Such ignition is essential to the operation of high efficiency internal combustion engines using the more difficult to ignite dilute mixtures, such as lean mixtures, high residual or high EGR mixtures, and fuel-air mixtures of the more difficult to ignite fuels such as the alcohol fuels. Such high power, high energy ignition delivers power to the mixture at the rate of hundreds of watts versus tens of watts for conventional inductive ignition and conventional capacitive discharge ignition. Total useful energy delivery to the mixture ranges from about fifty millijoules to several hundred millijoules, versus five to twenty millijoules for conventional ignitions.
The ignition is usable in the simpler distributor form or in a distributorless ignition form preferably achieved by the use of a separate leakage inductor disclosed in U.S. patent application Ser. No. 7-350945, now abandoned and U.S. Pat. No. 5,131,376. The high power/high energy feature is attained by the use of the voltage doubling principle disclosed in U.S. Pat. No. 4,677,960 and its improvements. The ignition control system is based in part on U.S. Pat. Nos. 4,688,538 and 5,131,376. U.S. Pat. Nos. 4,774,914, 4,841,925, 4,868,730, and 5,207,208 may also be relevant to other features of the invention. The said application and all said patents are of common assignment with this application.
Reference to the above cited application and patents is sometimes made herein by simply listing the last three numerals of the number, as in patent application '945, and patent number '376, '960, '538, '914, '925, '730, and '208.